In a cutting device, when a cutting machining is performed with a cutting tool, such as a cutting tool or the like, on a workpiece made of a difficult-to-cut material, such as Titanium alloy or Inconel, a cutting edge of the cutting tool is kept in contact with the workpiece for a long time with a large cutting resistance force. Accordingly, cutting heat at a high temperature tends to be generated at the contacting portion of the cutting edge. This may cause a deterioration of the tool life.
Under such situation, a rotary cutting method has been proposed, for example, in a Patent Literature 1, in which a rotation axis of a rotatable round-plate shaped cutting tool is arranged in parallel with a cutting traveling direction and the cutting machining is performed on the workpiece, with rotation of the cutting tool, making an end surface of the cutting tool functioning as a rake surface. According to this rotary cutting method, since the cutting tool is rotated, the cutting heat generated on the cutting edge is dispersed in the entire circumference, thereby to improve the tool life.